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An ocean zone nobody knew existed, which is home to more than 100 new species, has been discovered by Oxford University.

The Rariphotic Zone, or rare light zone, extends from 226 feet (130m) to 984ft (300m) and joins five other areas which have distinct biological communities living and growing within them.

The new section, was discovered during a research mission to Bermuda organised by the British charity for ocean exploration Nekton, and led by marine research scientists from Oxford University.

As well as the new zone, more than 100 new species were discovered including tanaids – minute crustaceans - dozens of new algae species and black wire coral that stand up to two metres high.

The survey team spent hundreds of hours underwater, either scuba diving or using submersibles and remote operated vehicles which can reach depths of 6,500 feet (2,000m).

The diving and submersible team off the Bermuda coast Credit:
Nekton

“Considering the Bermudian waters have been comparatively well studied for many decades, we certainly weren’t expecting such a large number and diversity of new species,” says Alex Rogers, Professor of Conservation Biology at Oxford University and scientific director of Nekton.

Prof Rogers said the discovery of a whole new ocean zone, teeming with life, shows that there could be far more ocean species, and of greater variety than previously thought.

“The average depth of the ocean is 4,200m. If life in the shallower regions of the deep sea is so poorly documented it undermines confidence in our existing understanding of how the patterns of life change with depth,” he added.

“[This is] evidence of how little we know and how important it is to document this unknown frontier to ensure that its future is protected”.

The antillogorgia sea fan, found at a depth of 100 feetCredit:
Nekton

The group also discovered a major algal forest on the summit of an underwater mountain 15 miles off the coast of Bermuda.

The undersea mountain’s slopes were found to harbour gardens of twisted wire corals and sea fans, communities of sea urchins, green moray eels, yellow hermit crabs, small pink and yellow fish and other mobile fauna.

There are more than 100,000 underwater mountains in seas across the globe yet less than 50 have been biologically sampled in detail.

The group's next mission will be to the Indian Ocean later this year, diving in seas around the Seychelles, the Maldives, Mauritius, Andaman and Sumatra.

Researchers said it showed the oceans are more populated and diverse than previously thought Credit:
Nekton

Oliver Steeds, chief executive of Nekton, said: “24 people have been to the moon; we have played golf on the moon, yet only three people have ever descended to the nadir of our Earth, 11,000m, to full ocean depth.

“We now have the technology available to us to discover the deep ocean, to discover more of our planet in the next 10 years than we have in the last 100,000. We have been looking up and when we should have been looking down.”

In March 2018, in the scientific journal Nature Scientific Reports, Dr. Carole Baldwin from the Smithsonian Institute described the discovery of unique reef-fish communities living above the seabed between 130 and 309 meters around the Caribbean island of Curacao that are taxonomically distinct from shallower animals.

Lacking an existing name for this depth zone Dr. Baldwin proposed ‘rariphotic'. Results from Nekton's XL Catlin Deep Ocean Survey in Bermuda confirms that a similar zonation of life exists in the water column, and provides additional evidence of this zonation within the biota of the seabed including corals, sponges and algae.